Speaking on the sidelines of a function here, Dr Mahatir said regulations for gold trading was important as the precious yellow metal was traded in high value.

He said gold trading firm, Genneva Malaysia Sdn Bhd, should be investigated thoroughly on the firm's trading activities.

Genneva Malaysia was among four gold trading companies raided by the authorities, including Bank Negara Malaysia, on suspected offences like illegal deposit-taking, money laundering and tax evasion.

Other gold trading companies raided were Pageantry Gold Bhd, Caesar Gold Sdn Bhd and Worldwide Far East Bhd. Dr Mahathir said Genneva should be investigated to find out exactly what they did that was wrong.

Asked whether the decision to investigate gold trading companies for suspected offences would cause a backlash to the government, Dr Mahathir said: "I feel that we should circumspect when taking a decision without fully appreciating the problem. Must investigate first."